This book serves the environmentalists to track the development of photocatalytic materials and technology in the present context and to explore future trends. Photocatalysis is the most influential greener technology being researched, developed and adopted for the treatment of wastewater. The technological advancements in the area of smart hybrid photocatalytic materials have gained momentum in the present era. The rational designing of photocatalytic materials with a multi-pronged approach opens a new chapter for environmental detoxification. Other important aspects relate to the transfer of this nanostructured photocatalytic technology to real backdrops. Harnessing natural solar energy for energy and environmental roles is another crucial criterion in designing photocatalysts.